Liquid crystal device and electronic apparatus

• US 10,088,727 B2
• Filed: 10/21/2016
• Issued: 10/02/2018
• Est. Priority Date: 10/29/2015
• Status: Active Grant

• Current Assignee: 138 East LCD Advancements Limited (Vector Capital Corporation)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Wada, Masayuki, Nakagawa, Masashi
• Primary Examiner(s): PAN, JIA X
• Application Number:
  US15/331,007
• Publication Number:
  US 20170123250A1
• Time in Patent Office: 711 Days
• CPC Class Codes: G02F 1/136209 Light shielding layers, e.g. black matrix, incorporated in the active matrix substrate, e.g. structurally associated with the switching element
• CPC Class Codes: G02F 1/136218 Shield electrodes
• CPC Class Codes: G02F 1/136227 Through-hole connection of the pixel electrode to the active element through an insulation layer
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G02F 1/13685 Top gates
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 29/42384 for thin film field effect transistors, e.g. characterised by the thickness or the shape of the insulator or the dimensions, the shape or the lay-out of the conductor
• CPC Class Codes: H01L 29/786 Thin film transistors, i.e. transistors with a channel being at least partly a thin film transistors having only the source or the drain region on an insulator layer H01L29/0653; thin film FinFETs H01L29/785
• CPC Class Codes: H01L 29/78633 with a light shield
• CPC Class Codes: H01L 29/78696 characterised by the structure of the channel, e.g. multichannel, transverse or longitudinal shape, length or width, doping structure, or the overlap or alignment between the channel and the gate, the source or the drain, or the contacting structure of the channel H01L29/78612 takes precedence; transistors having a drain offset region or a lightly doped drain [LDD] H01L29/78621

Abstract

A liquid crystal device includes: a liquid crystal layer disposed on a first substrate; a first light shielding layer disposed between the first substrate and the liquid crystal layer; a second light shielding layer disposed between the first light shielding layer and the liquid crystal layer; a first transistor provided in a display region; and a second transistor provided in a peripheral region that is a region around the display region, in which the first transistor is disposed so as to overlap with at least the second light shielding layer in a plan view, and in which the second transistor is disposed so as to overlap with at least the first light shielding layer in a plan view.

Claims

1. A liquid crystal device, comprising:

a substrate;

a liquid crystal layer disposed on the substrate;

a first light shielding layer disposed between the substrate and the liquid crystal layer;

a second light shielding layer disposed between the first light shielding layer and the liquid crystal layer;

a first transistor provided between the second light shielding layer and the liquid crystal layer in a display region; and

a second transistor provided between the first light shielding layer and the liquid crystal layer in a peripheral region that is a region around the display region,

wherein the first transistor overlaps with at least the second light shielding layer in a plan view, and

wherein the second transistor overlaps with at least the first light shielding layer in the plan view, and

wherein the first light shielding layer and the second light shielding layer are electrically connected to a gate electrode of the first transistor by one contact hole.

2. The liquid crystal device according to claim 1, wherein the first transistor overlaps with the first light shielding layer and the second light shielding layer in the plan view.

3. The liquid crystal device according to claim 1,

wherein at least one of the first light shielding layer and the second light shielding layer is made of a material having a light reflection property.

4. The liquid crystal device according to claim 3,

wherein materials of the first light shielding layer and the second light shielding layer are tungsten silicide.

16. An electronic apparatus comprising:

the liquid crystal device according to claim 1.

17. An electronic apparatus comprising:

the liquid crystal device according to claim 2.

18. An electronic apparatus comprising:

the liquid crystal device according to claim 3.

19. An electronic apparatus comprising:

the liquid crystal device according to claim 4.

5. A liquid crystal device comprising:

a first substrate;

a second substrate disposed opposite to the first substrate;

a liquid crystal layer interposed between the first substrate and the second substrate;

a switching element including a semiconductor layer that is disposed on the first substrate for each pixel and includes a channel region, a gate insulating layer covering the semiconductor layer, and a gate electrode disposed opposite to the channel region via the gate insulating layer;

a first light shielding layer that is disposed on the first substrate and overlaps with the semiconductor layer in a plan view and is set to the same potential as the potential of the gate electrode;

a first insulating layer that covers the first light shielding layer;

a second light shielding layer that is disposed on the first insulating layer and overlaps with the semiconductor layer and the first light shielding layer in the plan view and is set to the same potential as the potential of the gate electrode; and

a second insulating layer that covers the second light shielding layer,

wherein the first light shielding layer, the first insulating layer, the second light shielding layer, and the second insulating layer are provided between the first substrate and the semiconductor layer.

6. The liquid crystal device according to claim 5,

wherein the first light shielding layer or the second light shielding layer is formed straddling a boundary between two pixels.

7. The liquid crystal device according to claim 5,

wherein the first light shielding layer or the second light shielding layer is formed to be separated for each pixel.

8. The liquid crystal device according to claim 5, further comprising:

a first contact hole and a second contact hole that penetrate the first insulating layer and electrically connect the first light shielding layer and the second light shielding layer,

wherein the first contact hole and the second contact hole are disposed at both outsides of the semiconductor layer in a direction intersecting the extending direction of the semiconductor layer in the plan view.

9. The liquid crystal device according to claim 8,

wherein the second light shielding layer fills the first contact hole and the second contact hole, and has a substantially flat surface.

10. The liquid crystal device according to claim 9, further comprising:

a third contact hole and a fourth contact hole that penetrate the gate insulating layer and the second insulating layer and electrically connect the gate electrode and the second light shielding layer,

wherein the third contact hole overlaps with the first contact hole in the plan view, and the fourth contact hole overlaps with the second contact hole in the plan view.

11. The liquid crystal device according to claim 5, further comprising:

a fifth contact hole that penetrates the first insulating layer and electrically connects the first light shielding layer and the second light shielding layer,

wherein, in the sectional view taken along the extending direction of the semiconductor layer, the second light shielding layer is disposed across the bottom portion and the side portions of the fifth contact hole, and the surface of the first insulating layer positioned at the outsides of the fifth contact hole, and

wherein, in the sectional view taken along the extending direction of the semiconductor layer, the semiconductor layer covers the second light shielding layer via the second insulating layer.

12. The liquid crystal device according to claim 11,

wherein at least the channel region of the semiconductor layer is disposed at the bottom portion of the fifth contact hole.

13. The liquid crystal device according to claim 11, further comprising:

a third contact hole and a fourth contact hole that penetrate the gate insulating layer and the second insulating layer and electrically connect the gate electrode and the second light shielding layer,

wherein the third contact hole and the fourth contact hole are disposed at both outsides of the semiconductor layer in a direction intersecting the extending direction of the semiconductor layer in the plan view.

14. The liquid crystal device according to claim 6, further comprising:

a plurality of contact holes that penetrate the first insulating layer and electrically connect the first light shielding layer and the second light shielding layer,

wherein the number of the contact holes is less than the number of the pixels.

15. A liquid crystal device, comprising:

a substrate;

a liquid crystal layer disposed on the substrate;

a first light shielding layer disposed between the substrate and the liquid crystal layer;

a second light shielding layer disposed between the first light shielding layer and the liquid crystal layer;

a first transistor provided between the second light shielding layer and the liquid crystal layer in a display region; and

a second transistor provided between the first light shielding layer and the liquid crystal layer in a peripheral region that is a region around the display region,

wherein the first transistor overlaps with at least the second light shielding layer in a plan view,

the second transistor overlaps with at least the first light shielding layer in the plan view,

at least one of the first light shielding layer and the second light shielding layer is made of a material having a light reflection property, and

materials of the first light shielding layer and the second light shielding layer are tungsten silicide.